Abstract:

A device for assembling a lens into a lens barrel is provided. The device
includes a pressing rod and a sensing module positioned above the
pressing rod. The pressing rod includes a first end and a second end
opposite to the first end. The first end defines a first surface for
pressing against the lens. The second end defines a second planar end
surface. The sensing module includes a pressing surface for facing toward
the second planar end surface, a number of force sensors mounted on the
pressing surface, each force sensor being configured for sensing a
counterforce applied thereto when the force sensors are pressed against
the second planar end surface of the pressing rod.

Claims:

1. A device for assembling a lens into a lens barrel, the device
comprising:a pressing rod comprising a first end and a second end
opposite to the first end, the first end defining a first surface for
pressing against the lens, the second end defining a second planar end
surface; anda sensing module comprising:a pressing surface for facing
toward the second planar end surface; anda plurality of force sensors
mounted on the pressing surface, each force sensor being configured for
sensing a counterforce applied thereto when the force sensors are pressed
against the second planner end surface of the pressing rod.

2. The device as claimed in claim 1, wherein the sensing module comprises
a display for displaying the counterforce sensed by each force sensors.

3. The device as claimed in claim 1, wherein the pressing rod is
cylindrical in shape.

4. The device as claimed in claim 2, wherein the sensing module comprises
a pressing plate with the force sensors mounted thereon and a handle
fixed to an opposite side of the pressing plate to the force sensors.

5. The device as claimed in claim 4, wherein the pressing plate has the
pressing surface, which is circular in shape, the force sensors being
equadistantly distributed around an imaginary circle.

6. The device as claimed in claim 4, wherein the display comprises a
converter and a display screen, the converter being received in the
handle and configured for converting the signals from the force sensor
into display information associated with the counterforces, the display
screen being mounted on the handle and configured for displaying the
counterforces.

7. The device as claimed in claim 6, wherein the display screen includes
at least one emitting diode panel.

8. The device as claimed in claim 1, wherein the force sensors are made
from pizeoelectrical material.

9. The device as claimed in claim 8, wherein the pizeoelectrical material
is selected from the group consisting of: piezoelectric ceramic,
piezoelectric crystal and piezoelectric polymeric.

10. A process for assembling a lens in a lens barrel comprising:orienting
a lens barrel such that an optical axis thereof is perpendicurlar to a
horizontal direction;disposing a lens in the lens barrel;pressing the
lens toward the lens barrel using a substantially vertically oriented
pressing rod, the pressing rod having a first end for abutting against
the lens, and an opposite second end; andpressing the pressing rod using
a sensing module, the sensing module comprising a pressing flat surface,
and a plurality of force sensors mounted on the pressing flat surface,
the pressing flat surface being horizontally oriented and facing toward
the second end of the pressing rod, each of the force sensors being
configured for pressing against the second end of the pressing rod and
sensing a counterforce applied thereto by the second end.

11. The process as claimed in claim 10, wherein the process further
comprising reorienting the lens to a vertical orientation based on the
sensed counterforces.

Description:

BACKGROUND

[0001]1. Technical Field

[0002]The present invention generally relates to devices for assembling
lens modules and, particularly, to a device and a method for assembling a
lens to a lens barrel.

[0003]2. Description of Related Art

[0004]Nowadays, lens modules typically include a lens barrel and lenses
received in the lens barrel. With the progress of the technology, it is
required that the lens modules should be small in size and have a high
imaging quality. As well known, the imaging quality of the lens modules
is mainly depended on the assembling preciseness of the lens modules. In
general, the assembling process of a lens module includes: picking up the
lens and putting it into the lens barrel using a sucking apparatus; and
pressing the lens into the lens barrel using a rod. The disadvantage of
the above assembling process is that during the assembling process, it is
difficult to inspect the position/angle of the lens relative to the
optical axis of the lens barrel, thus the lens may not be accurately
positioned in the lens barrel. As a result, the imaging quality of the
lens module cannot be guaranteed.

[0005]What is needed, therefore, is an device for assembling a lens into a
lens barrel, which can overcome the above mentioned problems.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006]FIG. 1 is an isometric, schematic view of a device including a
sensing module, according to an exemplary embodiment.

[0007]FIG. 2 is a bottom plan view of the sensing module of FIG. 1.

[0008]FIG. 3 is a partially sectional view showing a process of assembling
a lens into a lens barrel using the device of FIG. 1.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0009]Referring to FIG. 1, a device 10 is shown. The device 10 includes a
pressing rod 100 and a sensing module 200 positioned above the pressing
rod 100. The pressing rod 100 includes a first end 101 and a second end
102 opposite to the first end 101. The first end 101 defines a first
surface 1011 for pressing against the lens. The second end 102 defines a
second planar end surface 1021. The sensing module 200 includes a
pressing surface 201 for facing toward the second planar end surface
1021, a number of force sensors 202 mounted on the pressing surface 201,
each force sensor 202 being configured for sensing a counterforce applied
thereto when the force sensors 202 are pressed against the second planar
end surface 1021 of the pressing rod 100.

[0010]The first end 101 is cylindrical in shape. The second end 102 is
also cylindrical in shape, and the diameter of the second end 102 is
greater than the diameter of the first end 101. The shape of the second
end 102 is not restricted to cylinder, other shapes such as elliptical
cylinder or prism can also be alternatively adapted.

[0011]The sensing module 200 includes a pressing plate 203 with the force
sensor 202 mounted thereon and a handle 204 fixed to an opposite side of
the pressing plate 203 to the force sensors 202, and the sensing module
200 further includes a display 205 for displaying the counterforce sensed
by each force sensor 202.

[0012]The pressing plate 203 has the pressing surface 201, the shape of
the pressing surface 201 is substantially the same as the second planar
end surface 1021 of the pressing rod 100.

[0013]Each of the force sensors 202 is used for sensing a counterforce
acted thereupon by the pressing rod 100. Referring to FIG. 2, the
pressing surface 201 is circular in shape, the force sensors 202 are
equadistantly distributed around an imaginary circle. The number of the
force sensors 202 is four in this embodiment, but can vary depending on
requirements in other alternative embodiments. The force sensors 202 are
made from pizeoelectrical material such as piezoelectric crystal or
piezoelectric polymeric.

[0014]The display 205 is electrically connected to the force sensors 202.
The display 205 includes a converter (not shown) received in the handle
204 for converting the voltage signals from the force sensors 202 into
display information associated with the sensed counterforces, and a
display screen 2051 mounted on the handle 204 and configured for
displaying the counterforces.

[0015]The display screen 2051 includes at least one light emitting diode
panel 20511. In this embodiment, the number of the light emitting diode
panels 20511 is equal to the number of the force sensors 202. Each light
emitting diode panel 20511 is configured for displaying a counterforce
value transmitted from a force sensor 201. Also the four light emitting
diode panels 20511 can be replaced with a single light emitting diode
panel capable of displaying all the counterforce values thereon. That is,
the number of the light emitting diode panels is not limited to this
embodiment.

[0016]Referring to FIG. 3, in operation, a lens barrel 22 is oriented
substantially perpendicularly to a horizontal direction. Then a lens 21
is picked up by a sucking apparatus (not shown) and is disposed in a lens
barrel 22, and the lens is pressed toward the lens barrel by using the
substantially vertically oriented pressing rod 100. Next, the device 10
is used for detecting whether the lens 21 is tilted relative to the
barrel 22 before the lens 21 is pressed into the barrel 22. The sensing
module 200 is supported by a mechanical arm (not shown) so that the
bottom surfaces of the force sensors 202 can be kept at a same horizontal
surface. The mechanical arm drives the sensing module 200 to the pressing
rod 100. When the counterforce values displayed by the display 205 does
not equal to each other, the lens 21 and the pressing rod 100 are tilted
relative to the lens barrel 22. The orientation of the lens 21 can then
be adjusted until the counterforce values displayed by the light emitting
diode panels 20511 are equal to each other, before that, the pressing rod
100 must be reoriented to a vertical orientation. Therefore, the device
10 can precisely measure the orientation of the lens 21 in the lens
barrel 22.

[0017]The lens 21 includes a central imaging portion 211, accordingly, the
first surface 1011 further defines a recess 1012 aligned with the central
imaging portion 211, and a periphery portion 212. When assembling the
lens 21 into the lens barrel 22, the periphery area 212 contacts the
first end 101 of the pressing rod 100. The lens 21 is then pressed into
the lens barrel 22 by the press rod 100.

[0018]It is believed that the present embodiments and their advantages
will be understood from the foregoing description, and it will be
apparent that various changes may be made thereto without departing from
the spirit and scope of the invention or sacrificing all of its material
advantages, the examples hereinbefore described merely being preferred or
exemplary embodiments of the invention.